Ellison has made foundational contributions in the areas of computer-mediated communication, mediated interpersonal interaction, self-presentation, use of social media in organizations, relationship initiation and maintenance in online contexts, and online dating sites. Her 2007 and 2013 articles on social network sites (with danah boyd)[2] have over 15,000 citations. Her work on Facebook relationship maintenance has been cited by and adopted in a variety of scholarly articles, and she is frequently sought as a speaker, advisor, and collaborator in these areas. She received a grant from the National Science Foundation in 2009 to pursue her work on "the role of social network sites in facilitating collaborative processes". She also received a grant from the Bill & Melinda Gates Foundation and the College Knowledge Challenge group to explore the potential for social media to address college-going behaviors among low-income and first-generation college students.

Ellison is frequently sought for expert commentary on social media. She has been quoted in mainstream news articles on popular social media sites like Facebook[3] and Snapchat,[4] on news and social media,[5] and on relationships and social media.[6]